Final answer:
Approximately 0.8 moles of KNO3 would dissolve in the saturated solution.
Step-by-step explanation:
To find the number of moles of KNO3 that would dissolve in a saturated solution, we need to calculate the moles of KNO3 in 200 g of water.
Firstly, we need to convert the mass of water to moles by using the molar mass of water (H2O), which is approximately 18 g/mol. So, 200 g of water is equal to 200 g / 18 g/mol = 11.1 mol.
Next, we can use the solubility of KNO3 to determine the moles of KNO3 that dissolve in 100 g of water. The solubility of KNO3 is 40.0 g/100 g water. Therefore, for 200 g of water, the moles of KNO3 would be 2 * (40.0 g/100 g) = 0.8 mol.
Therefore, approximately 0.8 moles of KNO3 would dissolve in the saturated solution containing 200 g of water at 25°C.